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Circuit/System Testing

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Liftglass Release Switch Malfunction

  1. Ignition OFF, disconnect the harness connector at the liftglass release switch.
  2. Test for less than 5 Ω between the ground circuit terminal B and ground.
    • If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Ignition ON, verify the scan tool Ext. Trunk/Liftglass Rel. Sw parameter is Inactive.
    • If not the specified value, test the signal circuit terminal A for a short to ground. If the circuit tests normal, replace the BCM.
  4. Connect a 3A fused jumper wire between the signal circuit terminal A and ground, verify the scan tool Ext. Trunk/Liftglass Rel. Sw is Active.
    • If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.
  5. If all circuits test normal, test or replace the liftglass release switch.

Liftglass Latch Assembly Malfunction

  1. Ignition OFF, disconnect the harness connector at the rear window wiper motor.
  2. Ignition ON, connect a test lamp between the signal circuit terminal B and ground.
  3. Command the liftglass latch to release by pressing the liftgate window release switch. The test lamp should briefly illuminate when the liftgate window release switch is pressed.
    • If the test lamp is always OFF, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
    • If the test lamp is always ON, test the signal circuit for a short to voltage. If the circuit tests normal, replace the BCM.
  4. Ignition OFF, connect the harness connector at the rear window wiper motor. Disconnect the harness connector at the liftglass latch assembly.
  5. Test for less than 5 Ω between the ground circuit terminal 2 and ground.
    • If greater than the specified range, test the ground circuit for an open/high resistance.
  6. Ignition ON, connect a test lamp between the control circuit terminal 1 and ground.
  7. Command the liftglass latch to release by pressing the liftgate window release switch. The test lamp should briefly illuminate when the liftgate window release switch is pressed.
    • If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal replace the rear window wiper motor.
    • If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal replace the rear window wiper motor.
  8. If all circuits test normal, test or replace the liftglass latch assembly.
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